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Finding the Fourth Proportional to 431.08, 646.22 and 391.80

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Solution

The fourth proportional to 431.08, 646.22 and 391.80 is: 587.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    431.08 : 646.22 = 391.80 : x
  2. Step 2: Convert to fraction form
    431.08/646.22 = 391.80/x
  3. Step 3: Cross multiply
    431.08x = 646.22 × 391.80
  4. Step 4: Simplify right side
    431.08x = 253,189.00
  5. Step 5: Solve for x
    x = 253,189.00/431.08
  6. Step 6: Final answer
    x = 587.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.